A Deluxe King at the Fairmont Copley Plaza is £348 per night plus tax. Book though a Virtuoso agent for amenities. Good location for shopping, but I'm not sure about shopping for high end furniture.
Virtuoso amenities:
- Upgrade on arrival, subject to availability
- Full breakfast daily for up to two in-room guests, in restaurant
- $100 USD equivalent Food & Beverage credit to be utilized during stay (not combinable, not valid on room rate, no cash value if not redeemed in full. Credit may be used towards OAK Long Bar + Kitchen, In Room Dining and Mini-Bar)
- Complimentary Wi-fi
- Early check-in/late check-out, subject to availability
Edit: just realized you were looking at £400 for 2 nights. This won't be a fit.